Thermocouple burner control



July 26, 1949. R. w. MUELLER THERMQCOUPLE BURNER CONTROL DEVICE 2 Sheets-Sheet 11 Filed Oct. 39, 1944 INVENTOR. @2502 W/VaeZ/er; v

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THERMOCOUPLE BURNER CONTROL DEVICE Filed Oct. 30, 1944 2 Sheets-Sheet 2 INVEN TOR.

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' w s m 26, 1949 Robert W. Mueller, Milwaukee, Wis., assignor to Milwaukee Gas Specialty Company, Milwaukee, Wis., a corporation of Wisconsin Application October 30, 1944, Serial No. 561,082

' Claims. (Cl. 137-144) This invention relates, in general, to a burner control device, and has particular relation to a thermocouple burner control device for fluid fuel burners,'which device is operable to shut down the main burner upon failure of the pilot flame.

The devicewhich I shall describe hereinafter in connection with the drawings is particularly I adapted for use with gas-fired floor furnaces of the type that are constructed to be set into the door, and have a register disposed, for example, at the floor level through which the heated air enters the room. It is to be understood, however, that the device of, the present invention is not limited to this particular use but may be employed for other purposes as suitable and desired.

It is known to provide floor furnaces and like apparatus with a combined shutoff valve and thermocouple safety device. In general, however, in prior devices of this sort two control rods have been required to operate the shutoff valve, reset the thermocouple safety device, and operate the pilot valve. As a result, the operation of the de vice has been more diflicult and its cost has been I higher.

One of the main objects of the present invention is to provide an improved form of thermocouple burner control device that may be manipulated very expeditiously from position above the floor.

Another object of the invention is to provide a device of the class described in which the shutoff valve is moved toopen, closed, and pilot positions, and in which the thermocouple safety means is adapted to be reset when the shutoff valve is in pilot position; all by means of a single rod connected to the shutoif'valve and the thermocouple safety device and extending to position to be operated, for example, from above the floor.

Another object of the invention is to provide, in a device of the class described, an operating member attached to the valve plug to turn the plug to open, closed, and pilot positions and having longitudinal movement relative to the plug for resetting the thermocouple safety device when the plug is in pilot position; the operating member being clear of the thermocouple safety device for longitudinal movement relative to the valve plug and free of the thermocouple safety device when the valve plug is out of pilot position,

Another object of the invention is to provide a device of this character having various features of novelty and advantages, and which is particularly characterized by its simplicity in construction, its economy in manufacture. its effectiveness in use, and the presence of only one operating rod for accomplishing the results set forth.

- Further objects and advantages of the invention will appear from the following detailed description, taken in connection with the accompanying drawings which illustrate the manner of constructing and operating one form of' deviceembodying the present invention.

In the drawings:

Figure 1 is an isometric sectional view of, a conventional floor furnace illustrating a thermocouple burner control device embodying the present invention applied thereto; I v

Figure 2 is a side elevational view of the thermocouple burner control device;-

Figure 3 is a top plan view of the device shown in Figure 2;

Figure 4 is an end view of the device taken from the right as the device is viewed in Figure 2;

' Figure 5 is an enlarged sectional view taken on the line 55 of Figure 3; and

Figure 6 is a fragmentary cross sectional view through the valve plug showing the pilot, open, and closed positions of the plug.

Referring now to the drawings, the invention is shown for purposesof illustration applied to a floor furnace which is designated in its entirety at it. The furnace l0, which may be of conventional or any suitable construction, is set into the floor H, and has a register I2 disposed, for example, at the floor level through which the heated air enters the room.

For purposes of the present description, sufllce it to state that the furnace I ll has a. main burner l3 which is supplied with gaseous fuel by a fuel a supply pipe l4 and that the thermocouple burner control device, designated in its entirety at 15, is

interposed in the fuel supply pipe M. The con-' struction of the floor furnace in per se forms no part of the present invention, and therefore it will not be described in further detail.

The thermocouple burner control device l5 comprisesa valve body or housing It having an inlet chamber I I, an intermediate chamber l8, and an outlet passage is. Contiguous sections of the fuel supply pipe H are connected to the inlet chamber l1 and outlet passage IS.

A wall or a partition 20 separates the inlet chamber I! from the intermediate chamber l8. This wall 20 has a valve opening 2|. An annular valve seat 22 is provided about the valve opening 2|, upon which valve seat 22 the yielding facing 23 of the thermocouple safety valve 24 is adapted to seat to shut ofi communication between the inlet and intermediate chambers l1 and I8 and asv'zgove thereby the supply of fuel for the main burner is; also the supply of fuel for a pilot burner 25, which pilot burner is positioned in proximity to the main burner i3 as shown in Figure 1.

screwed or otherwise secured at 26 in the valve body axially relative to the valve opening 26 is an electromagnet housing $1. The electromagnet 28 and armature 29 are disposed within the housing 27, and are preferably enclosed by an inner shell 30. A stem 35 has one end extending into the inlet chamber ll and attached to the thermocouple safety valve 25, preferably in a manner to permit self-accommodation of this valve to its seat 522. The opposite end of the stem 31 extends through the adjacent end of the shell as and is attached to the armature as, also preferably in a manner to permit self-accommonation of the armature to the pole ends of the magnet frame 32.

A coiled spring 33, interposed between the valve is and a spring abutment member 33, tends yieldingly to close the valve 124 and to hold it in closed position. Suitable sealing material 'is preferably placed around the stem 3| and between the member 3 3 and the adjacent end of the inner shell 39 to prevent the passage of dust or other foreign matter into the armature and electromagnet housing along the stem 3!.

The magnet frame 32 is secured, for example, to a terminal bushing 36 in the manner more fully disclosed in Henry F. Alfery Patent No. 2,318,136, May 4, 1943. The coil 3? of the electromagnet is wound around the legs of the magnet irame 32. The bushing 35 is shown as externally threaded for threaded engagement with a nut 33, by means. of which put the bushing 36 is clamped to the outer end of the electromagnet housing 2?.

A thermocouple, indicated at ll is placed in position so that the hot junction ll thereof will be heated by the pilot flame as long as the pilot flame is burning. The construction ofthethermocouple may be similar to that more fully disclosed in Oscar J. Leins Patent No. 2,126,554, August 9, 1938, or the construction of the thermocouple and leads therefor may be of any other suitable or preferred form.

The thermocouple lead comprises an outer tubular lead conductor s2 joined, for example, to the outer tubular thermocouple element and an inner lead conductor 83 joined to the inner thermocouple element as shown and described in the Leins patent above identified. The inner lead conductor as is insulated. from the outer lead conductor oz by a wrapping of insulation is on the inner lead conductor.

A quick detachable or removable connection is preferably provided between the ends of the leads *3? and 43 opposite the ends which are connected to the thermocouple elements. This removable lead connection may be in the form disclosed in the Henry F. Alfery patent above identified, and is illustrated in that form, it belngunderstood that this connection may be of any other suitable or preferred form. Sumce it, for purposes of this description, to state that the inner lead 43 has a connector cone which seats in the correspondingly recessed outer end of the terminal tip 36 and is clamped in contact therewith by a connector sleeve 41. The adjacent end of the outer tubular lead conductor 42 is connected in circuit with one side of the coil 31 through the bushing 36,- and the other side of the coil is connected to theinner lead conductor 43 through the terminaltip 4.6. r

The heat of the pilot light on the thermocouple so energizes the electromagnet 28 sumclently to hold the armature 29 in attracted position against the pole ends or the magnet frame 32 and the thermocouple safety valve is in open position, but this thermoelectric current is not capable of moving the armature is to attracted position and the valve is to open position. Reset means is therefore provided ror resetting or cooking the armature as to attracted position and the valve 25 to open position.

The reset means comprises a reset stem mounted for rectilinear movement in an opening 55 in the valve body it. The axis of the reset stem 56 is in alignment with the axis of the valve and armature stem 3!. A reset button 52 is secured to the outer end of the stem 50, for example by screwing the same thereon, as shown. The reset button 52 operates slidingly in the opening 5i in the valve body.

A guide member as is secured in the valve body is at the inner end of the opening s4. The inner end of the stem 59 extends through the guide 56 into the intermediate chamber 58 and is guided by the guide member 56. The opening in the guide as through which thestem 5d extends is sealed by suitable packing 55. A packing washer is provided at 55, and a coiled reset spring 57, interposed between the washer 5 and reset button 52, yieldingly holds the reset stern in the position shown in Figure 5, and returns the stem to this position upon release thereof, as will presently appear.

A gasket, or additional packing, may be provided at as, and the inner headed end of the reset stem 55 may have rib means at which cooperates with the gasket or packing so to press the same tightly about the stem additionally to prevent the escape of gas when the reset stem is in the position shown in Figure 5. A keri or slot so may be provided in the inner end of the stem as for screwing the stem into the button 52.

The shutoff or control valve is in the form of a truncated conical plug 55 seated in a conical bore 58 in the valve body it to turn to open. closed, and pilot positions, as shown in Figure 6; also to intermediate open and closed positions. The plug 55 is disposed laterally of the intermediate chamber 53 with its axis parallel with the axis of the valve and armature stem 35, and has laterally opening port means d? for cooperation with the outlet passage l9; also an outlet 5G opening from its inner end for supplying fuel to a pilot outlet 59 in the valve body it when the valve plug $5 is in the position shown in Figure 5. By reference to Figure 6 it will be apparent that turning of the plug $5 a quarter of a turn, or 90",

counterclockwise from the position shown will place the port means ill in position to open the passage 55 for the supply of fuel to the main burner. Another quarter or turn of the valve plug 51 in the same direction will shut ofi all fuel to both the main burner and the pilot burner. A

A pilot tube l2, connected to the pilot outlet 68 by suitable connection means 73. leads to the pilot burner 25 for the purpose of supplying fuel thereto when the valve plug 65 is in pilot position as shown in Figure 5.

A sleeve 15 is mounted in a cylindrical opening in the valve body H5 at the outer end of the conical bore 56. This sleeve 75 is held against outward displacement from the valve body by a plate 16 secured to the valve body, for example. by a screw H. The outer end of the sleeve ll has an inturned annular flange 18.

armors The valve-plug 95 has a stem II which extends outwardly from the valve body I. The valve plug 55 has an abutment l9, and adjacent this abutment II the valve stem 19 has an enlargement which is splayed at II. A combined abutment and stop member 92 has an opening which fits over the enlarged inner end of the stem 19 and is shaped to cooperate with the splayed portion ll thereof to prevent rotation oi the combined abutment and stop member 92 relative'to the valve stem 19. A coiled spring 94, interposed between the abutment and stop member 92 and abutment disc 95 which seats against the inturned annular flange l9, maintains the conical surface of the plug 65 resiliently and, at the same time, tightly seated in the bore 99. V

Rotation of the valve plug 95 in a counterclockwise direction (Figure 6)'is stopped when the valve plug is in full closed position, and'rotation of the plug in the opposite direction is stopped when it reaches full pilot position by cooperation of a radially extending finger 95 on the abutment and stop member 82, with stops 91 formed by the ends of an opening 99 in the sleeve 15. A set screw 99 holds sleeve 15 in position.

Turning of the valve plug 55 and resetting of the armature 29 to attracted position and valve 24 to open position is accomplished by means of an operating head 90. The operating head 95 has a bore 9| which fits slidingly over the adjacent end of the stem 19. The head 90 is connected to turn the stem 19, and thereby the valve plug 65, with turning movement of the operating head by means of the cavity in the head 90 which is mated to the stem 19 to connect stem 19 and thereby valve plug 55 for turning movement with head 99. A cross pin 92 fixed in the stem 19 limits the outward movement of head 90 relative to stem l9.

A finger 94, which extends laterally from the operating head 99, is adapted to register with the reset button 52 when the valve plug 65 is in pilot position as shown in Figure 5. In the illustrated embodiment of the invention the finger 94 is out of register with the reset button 52 in the other positions of the valve plug 55, namely, whenthe valve plug is in open and closed positions. The I longitudinal slots 93 permit longitudinal movement of the operating head 90 relative to the valve plug 55 inwardly from the, position shown in Figure 5.

With the finger 94 in register with the reset button 52 in the pilot position of the valve plug 65 the finger 94 engages the'reset button 52 in the inward longitudinal movement of the operating head 99, and imparts inward rectilinear movement to the reset stem 55 which, by engagement of its inner end with the valve means at 24, actuates the valve 24 to open position and the armature 29 to attracted position.

When the valve plug 65 is turned out of pilot position, for example, to open or closed positions, or to positions intermediate open and closed positions, the finger 94 is moved out of register with the reset button 52. Any inward longitudinal movement of the operating head 59 with the finger 94 out of register with the button 52 is free or clear of the reset button and, as a result, no resetting operation is'imparted to the reset means.

Turning and longitudinal movement are imparted to the operating head 90 by an operating rod 96 which extends up from the burner control device l5 to the fioor level. The rod 96 is provided at its upper end with an actuating handle end of the rod 99 is attached to the head II to turn same therewith and to impart the desired longitudinal movement to the head, for example, by securing the oblong or polygonal lower end of the rod 99 in a correspondingly shaped socket 95 in the head 99. l

A coiled spring I", interposed between the operating head 95 and the valve body l5, maintains the operating head 99 and rod 96 yieldingly in extended position as shown in Figure 5, and returns same to such position after the operating head 95 is depressed to reset the thermoelectric safety means. The operating head 95 may be provided with an annular recess lll2 for receiving the adjacent end of the spring I". The head preferably has openings I93 to permit insertion and removal of the cross pin 92.

To start the operation of the system shown in the drawings, the following sequence is followed:

With the valve plug 65 in pilot position as shown in Figure 5, the operating head up is pressed inwardly by means of the handle 91, and the finger 94 actuates the reset button 52 to move the valve 24 to open position and the armature 29 to attracted position. This sets up a flow of fuel to the pilot burner 25 through inlet chamber ll, valve opening 2|, intermediate chamber ll, the inner end of passageway l9', port 61, pilot outlet 69, and pilot tube 12. p v

Upon ignition of the pilot burner 25 forexample, by applying a lighted match or otherwise as desired, the pilot flame, by heating the hot junction 4i of the thermocouple 40, energizes the electromagnet 28 sufiiciently to hold the armature 29 in attracted position and the valve 24 open.

- open position as shown in Figure 6. Further 90 rotation of the valve plug 55 to closed position, as shown in Figure 6, will shut off all gas to both the main burner and the pilot burner, and the thermoelectric safety valve 24 will then, of course, close.

In order to place the unit in operation, the valve plug 55 is turned counterclockwise from its closed position (Figure 6) to pilot position and the described procedure is repeated. Intermediate positions of the valve plug 65 between open and closed positions will, of course, provide intermediate supplies of fuel to the main burner.

The embodiment of the invention shown in the drawings is for illustrative purposes only, and it is to be expressly understood that the drawings and the accompanying specification are not to be construed as a definition of the limits or scope of the invention, reference being had to the appended claims for that purpose.

I claim:

1. In a device of the class described, in combination, a fuel supply pipe, a controlling member, controlling the supply of fuel through said pipe, an electromagnet provided with an armature connected to said controlling member and adapted, when energized and said armature has been moved to attracted position to hold said member in operating position permitting the flow of fuel a valve plug mounted to be turned in cooperation with said valve body passagesto open, closed, and pilot positions, an operating member attached to said valve plu and having turning movement for turning the valve plug to different positions by turning movement of the operating member, said operating member being free for longitudinal movement relative to said valve plug in all of the positions into which said valve plug is adapted to be turned, and means on said operating member for registration with said reset means only when the valve plug is in pilot position and out of registration withsaidreset means in the other positions of said valve plugsaid reset means being so constructed and arranged that when the means on said operating member is in register with the reset means the reset means may be actuated to attracted positionwhereby said reset means is actuated by longitudinal movement of said operating member only when said valve plug is in pilot position and is not actuated by longitudinal movement of said operating member relative to said valve plug in the other positions of said .valve plug.

2. In a device of the class described, in combination, a control body having passages therein, a valve plug member rotatable .in said body in cooperation with said control body'passages to open, closed and pilot positions, a reset member mounted for reciprocatory movement in said body in position spaced laterally from the axis of said valve plug member, means requiring resetting and adapted to be reset by actuation of said reset member, an operating member connected to turn the valve plug member by turning movement of said operating member and free for longitudinal movement relative to the valve plug member in all of the positions into which said valve plug member is adapted to be turned, and abutment means integral with and extending laterally from said operating member, said abutment means registering with said reset member to actuate the reset member by longitudinal movement of the operating member relative to the valve plug member when said valve plug member is in pilot position and of a width along the path of turning movement of the operating member to be out of register with said reset member in all positions of said valve plug member except its pilot position, whereby longitudinal movement of said operating member relative to said valve plug member in positions other than pilot position will not actuate said reset member. v.

3. In a device of the class described, in combination, an electromagnet having a magnet frame and a coil, a thermoelectric generator connected in circuit with the coil of said electromagnet, an armature held attracted to said ma net frame by energization of said electromagnet by the heat of a flame on said thermoelectric generator and movable to retracted position upon extinguishment of the flame, a controlling member connected to said armature and held in operating position by said armature when the armature has been moved to attracted position and the electromagnet is energized by saidthermoelectric generator, means normally biasing said controlling member and the associated armature to safety position, a valve body having passages therein, a valve member mounted to be moved in cooperation with said valve body passages to open, closed and pilot positions, an operating member connected to said valve member and having movement for moving said valve member to its different positions by movement of said operating member, a reset member operable to reset "said armature to attracted position and said controlling member to operating position, said operating member being movable longitudinally relative to said valve member in all positions of said valve member, and means on said operating member for engagement with said reset member only in pilot position of, said valve member to reset said armature to attracted position and said controlling member to operating position by longitudinal movement of the operating member relative to the valve member in pilot position thereof.

4. In a device of the class described, in combination, an electromagnet having a magnet frame and a coil, a thermoelectric generator connected in circuit with the coil of said electromagnet, an armature held attracted to said magnet frame by energization of said electro-magnet by the heat of a flame on said thermoelectric generator and movable to retracted position upon extinguishment of the flame, a controlling member connected to said armature and held in operating position by said armature when the armature has been moved to attracted position and the electromagnet is energized by said. thermoelectric generator, means normally biasing said controlling member and the associated armature to safety position, a valve body having passages therein, a valve plug mounted for rotation in cooperation with said valve body passages to open, closed and pilot positions, an operating member connected to said valve plug and having movement for moving said valve plug to its different.

positions by movement or said operating member, a reset member operable to reset said armature to attracted position and said controlling member to operating position, said operating member being movable longitudinally relative to said valve plug in all positions of said valve plug,

and means on said operating member for engagement with said reset member only in pilot position of said valve plug to reset said armature to attracted position and said controlling member to operating position by longitudinal movement of the operating member relative to the valve plug in pilot position thereof, said reset member having reciprocatory movement along a path parallel with and spaced laterally from the axis of, said. valve plug.

5. In a device of the class described, in coinbination, an electromagnet having a magnet frame and a coil, a thermoelectric generator connected in circuit with the coil of said electromagnet, an armature held attracted to said magnet frame by energization of said electromagnet by the heat of a flame on said thermoelectric generator and movable to retracted position upon extinguishment of the flame, a controlling member connected to said armature and held in operating position by said armature when the armature has been moved to attracted position and the electromagnet is energized by said ture to safety position, a valve body havingpassages therein, a valve plug mounted for rotation engagement with said reset member only in pilot position of said valve plug to reset said armature to attracted position and said controlling member to operating position by longitudinal movement'oi the operating member relative to the valve plug in pilot position thereof, and an extended operating rod adapted for operation from remote position and connected to said operating 20 10 member to impart turning and longitudinal movement to said operating member.

ROBERT W. MUELLER.

nnrnnnncrzs crrnn The following references are of record in the file of this patent: r

UNITED STATES PATENTS Number Name Date 857,915 Woody June 25, 1907 1,898,952 Gray Feb. 21, 1933 2,226,313 Little Dec. 25, 1940 2,257,024 Ray Sept. 23, 1941 2,268,953 McGee l Jan. 6, 1942 2,299,649 Paille Oct. 20, 1942 2,318,136 Alfery May 4, 1943 2,318,823 Wantz May 11, 1943 2,324,862 Martin July 20, 1943 2,353,759 Ray July" 18, 1944 

